Plate type heat exchanger



Jan. 11, 1955 H. F. GOODMAN 2,699,324

PLATE TYPE HEAT EXCHANGER v Original Filed Jan. 9, 1950 s Sheets-Sheet 1 C .F/GJ. d

I 4 *1 ML 14 Inventor Attorneys Jan. 11, 1955 GOODMAN 2,699,324.

PLATE TYPE HEAT EXCHANGER Original Filed Jan. 9,4950 3 Sheets-Sheet 2 III I uvvew TOR By Hap/1 F GOQD M H. F. GOODMAN PLATE TYPE HEAT EXCHANGER Jan. 11, 1955 3 She'ts-Sheet 3 Original Filed Jan. 9, 195

VENTOR IN Haw; F. Geog/v44 BY i :AZ'TOR EKS United States Patent Ofifice 2,699,324 Patented Jan. 11, 1955 2,699,324 PLATE TYPE HEAT EXCHANGER Hugh Frederick Goodman, London, The A. P. V. Company Limited, British company Continuation of abandoned application Serial No. 137,619, January 9, 1950. This application April 28, 1952, Serial No. 284,743

Claims priority, application Great Britain January 13, 1949 4 Claims. (Cl. 257-245) England, assignor to London, England, a

promise between the two conditions.

The main object of this invention 1s to form of corrugated plate as will efliciency to be dealt with as flicting conditions.

A further object of the invention is to provide corrugated plates W ich will enable improved operating conditions to be obtained.

With the foregoing objects and still other objects in clauns.

In the drawings, Figure 1 is a vertical sectional elevation of a part of a heat exchanger incorporating plates made in accordance with this invention, this figure being a section taken on the line II of Fig. 2. Figure 2 shows a face elevation of a plate shown in the assembly of The heat exchanger frames are urged together, the plates having local projections 35 to hold th distance.

plate itself. Each of the plates is formed with ports which are indicated in Figure 2 at 22-25: these ports: are used, in

accordance with the normal practice as the inlet and outlet large corrugations and he purpose of this invention to obtain the benefits of both small and large corrugations.

Reference will now be made particularly to Figure 4 which shows to an enlarged scale the form of the plates 10 in accordance with this invention. The plates are corrugations having a pitch p and by providing in the flanks of the large corrugations small corrugations having a pitch p.

When the plates are assembled as is shown in Figures 1 and 4, the flow passages a, b,

form by reason of the large corrugations of pitch p.

Each small corrugation has relatively inclined sensibly plane Wall portions 16, 17 which are joined together at their apex by a crest portion 18 and at their bases by other base portions 19 to the next adjacent wall portion. The uppermost small corrugation on each large corrugation is shown as including a short flat wall portion 20 and the lowermost small corrugation of each large corrugation is connected to the lowermost small corrugation of the next adjacent large corrugation by a short flat wall portion 21, the wall portions 20 and 21 being parallel with the plane of the plate.

It will be clear from Figures 1 and 4 that the small corrugations of pitch p cooperate to form chambers (indicated by the reference 14) connected by restricted passages 15' the passages 15' directing the fluid flow against the wall of the chambers 14 while at the same time the fluid is caused to have velocity and directional changes, the changes in direction arising not only on account of the small corrugations but also on account of the sinuous nature of the flow passages a, b etc. themselves in following the large corrugations of pitch p. Because each large corrugation embraces a number of small corrugations, the heat transfer efficiency is maintained at the same time that the required mechanical strength is given to the plates. Thus by reason of the invention the rigidity or stiifness of the plates can be determined by the larger corrugations and the pitch and the form of the small corrugations can be selected purely on the basis of the heat exchange requirements so that the overall efficiency and performance of such a heat exchanger will be increased.

The invention provides other advantages: it enables a heat exchanger using such plates to be maintained in a clean condition more easily for the reason that the corrugations are more open so permitting easy brushing: when the plates are, as is it would permit thinner metal to be employed 1n view of the rigidity or stiffness which is imparted by the large corrugations: in cases in which a metal of low ductility is employed the form of corrugation according to this invention will be easier to produce by pressing without danger of fracture of the metal.

There is also the further important advantage that for a given stiffness of plate and rate of heat transfer, plates made in accordance with the invention may have a substantial minimum clearance between them, this benefit minimizing the risk of choking the flow passages, either because of the large particles which may sometimes be carried by the liquids or because of the tendency of some liquids to build up a coating on the surfaces of the plates.

The pitch p of the large as shown, be greater than their depth h. may be from two to six times pitch p of the smaller corrugations may be greater than their depth h, as also shown in Figure 4. The pitch p of the small corrugations may be about one third to one eighth of the pitch p of the large corrugations and the depth h' of the small corrugations may be one quarter to one twentieth of the depth h of the large corrugations. Preferably the pitch size and depth of the respective corrillgations in one plate are identical with those in adjacent p ates.

It is to be observed that the provision of the small corrugations does not materially, if at all, provide any increased stiffness against deformation under the pressure of the liquid, but serves mainly the purpose of promoting a higher rate of heat transfer or, for a given rate heat transfer, an increased minimum spacing between adjacent plates.

As illustrated in Figure 3, the ends 30 of the large corrugations can be outwardly inclined towards the marginal recess or channel 28. In the arrangements illustrated the plates are produced by pressing metal sheets, for example, of copper or stainless steel, and if the large corrugations extend abruptly to the inner edge of the channel 28 there is a tendency towards breaking during the pressing operation. To avoid this, the large corrugations may nate a short distance from the channel 28, as illustrated at 31 in Figure 5. However, when constructed in this way, the assembled plates would leave channels extending along the marginal portions of the plates parallel to the sides of the gasket recess 28 and through which the liquids tend to by-pass thereby reducing the overall efficiency of the plates.

To eliminate or reduce this tendency, according to a further feature of the invention, a small corrugation 32 (Figure is provided in each end 30 of each large corrugation, this corrugation 32 extending down from the upper edge of the corrugation to the inner edge of the recess 28, the remainder of the end of the corrugation termrterminating short of the said edge of recess 28. The corrugations 32 may, as shown, he continuations of the small corrugation at the crest of each large corrugation. These small end corrugations 32 of adjacent plates provide restrictions in the flow passage formed between the ends of the plates: these restrictions restrict the flow and produce a change in direction of liquids tending to by-pass the plates adjacent to the recess 28, and thus minimize or eliminate this. The two end walls of the apparatus are respectively formed with depressions and projections inter-mating with the large and small corrugations in the adjacent plates.

1 claim:

1. A heat exchanger comprising an assemblage of plates each having flow openings which are spaced apart along the length of the plate which has extending across the width of the plate large stiffening corrugations which have end walls extending down to the marginal edge portions of the plate, the side walls of the large corrugations being formed with small corrugations along the length of and parallel with the large corrugations and the end walls of the large corrugations being formed with at least one small corrugation and means securing the plates in spaced face-to-face relationship with the large and small corrugations similarly directed and parallel so that the large corrugations of adjacent plates not only stiffen the plates but also cooperate to provide between each pair of plates flow channels of sinuous form extending transversely across the flow path from opening to opening while the small corrugations in the side walls cooperate to constitute each sinuous flow passage as a succession of chambers connected by restrictions which produce changes in velocity of the fluid flow, the small corrugations in the end walls of the large corrugations cooperating to provide restrictions to the flow of fluid between the end walls of adjacent plates.

2. A heat exchanger comprising an assemblage of plates each having flow openings which are spaced apart along the length of the plate and which has extending across the width of the plate large stiffening corrugations which have end walls extending down to a sealing compo nent at the marginal edge portions of the plate, the side walls of the large corrugations being formed with small corrugations along the length of and parallel with the large corrugations and the end walls of the large corrugations being formed with at least one small corrugation, and means securing the plates in spaced face-to-face relationship with similarly directed and parallel so the large corrugations of adjacent plates not only stiffen the plates but also cooperate to provide between each pair of plates fiow channels of sinuous form extending transversely across the flow path from opening to opening while the small corrugations in the side walls cooperate to constitute each sinuous flow passage as a succession of chambers connected by restrictions which produce changes in velocity of the fluid flow, the small corrugations in of the large corrugations cooperating to provide restrictilons to the flow of fluid between the end walls of adjacent p ates.

3. A heat exchanger comprising an assemblage of plates each having flow openings which are spaced apart along the length of the plate and which has extending across the width of the plate large stiffening corrugations which have sloping end walls extending down to a sealing component at the marginal edge portions of the plate, the side walls of the large corrugations being formed with small corrugations along the length of and parallel with the large corrugations and the sloping end walls of the large corrugations being formed with at least one small corrugation, and means securing the plates in spaced face-to-face relationship with the large and small corrugations similarly directed and parallel so that the large corrugations of adjacent plates not only stiffen the plates but also cooperate to provide between each pair of plates flow channels of sinuous form extending transversely across the flow path from opening to opening while the small corrugations in the side walls cooperate to con stitute each sinuous flow passage as a succession of chambers connected by restrictions which produce changes in velocity of the fluid flow, the small corrugations in the sloping end walls of the large corrugations cooperating to provide restrictions to the flow of fluid between the end walls of adjacent plates.

4. A heat exchanger comprising an assemblage of plates each having flow openings which are spaced apart the length of and parallel with the large corrugat1ons and the end walls of the large corrugations being formed with the large corrugations, and

the corrugations of the plate similarly arallel so that the large corrugations of with at least one small corrugation, and means securing channels of sinuous form extending transversely across the plates in spaced face-to-face relationship with the the flow path from flow opening to large and small corrugations similarly directed and par- 10 the small corrugations of adjacent plates cooperate to end WQHS Of the large corrugations cooperating to pro- 20 2,090,222

vidc restrictions to the flow of fiu1d between the end 2,181,230

Walls of adjacent plates. 2,550,339

5. A heat exchanger comprising an assemblage of similar plates having spaced flow openings and between the openings a number of large stiffening corrugations and 25 672,590

References Cited in the file of this patent UNITED STATES PATENTS Neveu Aug. 17, 1937 Groat Nov. 28, 1939 Ehrman Apr. 24, 1951 FOREIGN PATENTS Germany Feb. 16, 1939 

